Thursday, 17 February 2011

MS and CCSVI: the state of play

There is currently a lot of research going on, either directly into connections between CCSVI and MS or some of the issues around it. What I'm covering here is only a few of the studies I've noticed over the last month or so.

First, a very quick introduction, for those new to the subject.Over the last couple of years CCSVI (chronic cerebrospinal venous insufficiency) has become a "hot topic" in the MS community. The theory goes that rather than being an auto-immune condition, as is the received wisdom, MS is in fact caused by malformations of veins in the neck and trunk. These malformations lead to blood backing up in the brain, and consequent deposits of iron, which cause the immune system to attack the myelin coating the nerves.

If it is decided that there is a blockage, the area is widened using venoplasty or (on some occasions) stents. This has been termed the "Liberation Treatment". It's not without its risks: there have been complications, including deaths, particularly when stents have been used.

Large studies are currently in progress to establish whether there is a link between CCSVI and MS, and whether the "Liberation Treatment" is effective. Many people are not prepared to wait for the results of these studies, and are seeking treatment abroad, sometimes under rather dubious circumstances, as the clinic that diagnoses them as having blockages will also be charging them a large sum of money for the procedure.

So, some recent studies. I'll try to put them in some sort of logical order - not chronologically as they came out, but from diagnosis through symptoms and so on.

A clinically isolated syndrome (CIS) is an individual's first neurological episode, caused by inflammation or demyelination of brain tissue. It may be indicative of MS. In this study, a group of researchers in Italy scanned the veins of 50 patients with CIS, as well as groups of healthy controls and people with another neurological condition. There was no evidence of CCSVI in the patients with CIS. This result does not support the idea that there is any cause and effect relationship between CCSVI and MS.

A group of German researchers have found no supportive evidence for the presence of CCSVI in people with MS. They scanned the veins of people with MS and healthy controls, without knowing which was which, and found them equally likely to have blocked veins.

If CCSVI causes blockages in the veins draining the brain, you would expect there to be a back-up of blood in the brain, and therefore MS patients to have higher intercranial pressure than people without MS. German researchers have checked this, and found that MS patients have normal intercranial pressure. Again, this does not support the CCSVI hypothesis.

Most mammals (including us humans!) have a part of our genes called the major histocompatability complex (MHC for short). The molecules made by these genes play a large part in our immune systems and in auto-immunity. The MHC in humans is called HLA (human leukocyte antigen), and it comes in various "types", which are identified by letters and numbers. We already know that people with MS are more likely to have the type HLA DRB*1501. Now researchers in Buffalo, NY and Alabama have found that there is no association between HLA DRB*1501 and CCSVI. They suggest that the role of the underlying associations of CCSVI in MS should be treated with caution.

A positive result is of course a positive result, and I'm glad these people got relief from their fatigue: but it is of note that the studies which measured something objective found no evidence of a link between CCSVI and MS, while it was the study reporting a subjective, self-reported measure that did find a link.

Scans and treatments for CCSVI are carried out by Interventional Radiologists. The Cardiovascular and Interventional Radiological Society of Europe has issued a commentary on the treatment of CCSVI. It states that since no trial data are available, and the basis for the "Liberation Treatment" is anecdotal evidence and internet testimonies, this is not a sound basis on which to offer a new treatment.

Finally, an interesting commentary from Scientific American on how social media can shape medical practice. In this connected, internet-enabled age, doctors are playing catch-up. Even before Zamboni published the results of his first study, they had been posted on an internet forum along with useful links and a Facebook page. With MS, as with some other conditions, the problem is in knowing whether any improvement is really down to the treatment or to the natural ups and downs of the disease. It is vital for neurologists and other doctors to be aware of what patients are seeing and reading online.

Yes, interesting way of looking at it Chris. It has almost become like people's divine right to get the treatment. I've even heard people saying that if the scans show them as having clear veins, they'll still get the treatment done!

Search This Blog

Disclaimer

Comments from Funky Mango's Musings are to bring your attention to topics that could benefit you and should be discussed with your doctor or other medical professional. Posts are of a journalistic nature and are not in lieu of medical advice. Funky Mango's Musings will not be held liable for any damages incurred using the blog, data or links provided.